Valve assemblies of this type are used for mixing different liquids or gases. The valve manifold has a plurality of inflows through which different liquids or gases can be supplied, and one or more outflows through which the liquids or gases can be drained from the valve manifold. The inflows into the central mixing chamber and the outflows out of the central mixing chamber are controlled by diaphragm valves which can shut off the inflows into or the outflows from the central mixing chamber.
EP 0 972 148 B1, for example, discloses a diaphragm valve which is adapted to individually shut or open two inflows to and two outflows out of a central chamber, so that two inflows or outflows can be controlled by a common valve. A drawback of this design is that the central mixing chamber and the inflows and outflows are difficult to access, making maintenance and cleaning work very complicated. Above all when employed in the food industry and for operations in germ-free or sterile environments, a simple and rapid cleaning of a valve assembly is required.
Therefore it is important to provide a valve assembly which allows a simpler cleaning and maintenance of the valve manifold.